import java.util.Scanner;
public class Main1 {
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        String s=in.nextLine();
        String basicStr="aeiouAEIOU";
        int max=0;
        int temp=0;
        for (int i=0;i<s.length();i++){
            Character inputStr=s.charAt(i);
            Boolean isContainsBasic=basicStr.contains(inputStr.toString());
            if(isContainsBasic){
                temp++;
            }else{
                if(temp>max){
                    max=temp;
                }
                temp=0;
            }
        }
        System.out.println(max);
    }
}
